reference standard test

— The best available method of determining whether people have a condition

Synonyms:

gold standard, reference test

Full explanation:

The reference standard is the test, combination of tests, or procedure that is considered the best available method of categorising participants in a study of diagnostic test accuracy as having or not having a target condition.

Evaluations of diagnostic test accuracy require a comparison between the diagnostic test being evaluated (e.g. a rapid diagnostic test for malaria), which is referred to as the index test, and a reference standard used to categorise participants as having or not having the target condition (e.g. microscopy for malaria).